Nighttime and daytime conspicuity are vital to the safety of adults, children and their pets. Vehicles, including land and water vehicles, pedestrians, joggers, bikers and other sportsmen as well as pets need to be readily visible, especially under poor and/or low light conditions and in the darkness in order to avoid dangerous collisions. Certain occupations, such as traffic controllers, crossing guards, students, pedestrians and joggers, etc., need to be seen by the oncoming vehicles in the absence of good ambient lighting.
Traditionally conspicuity has been accomplished in two major ways: either via active illumination devices or via passive light management. Active illumination requires several key components: a power source, circuitry, light-emitting device(s) and a method of attachment or incorporation of the apparatus onto the substrate of the person, animal or item to be rendered more visible. Such approaches are outlined, for example in U.S. Pat. No. 6,964,493, U.S. Pat. No. 6,027,227, U.S. Pat. No. 7,377,663 and U.S. Pat. No. 6,834,395. These approaches are expensive and produce a cumbersome device that requires periodic servicing of its many parts, including replacement of the power source.
Passive light management is based on the principles of retroreflection. In this approach, incident light is manipulated so as to return its maximum intensity back to the source of the illumination. This is the principle behind reflective sheeting products found on, for example, road and traffic signs as well as protective gear, such as safety vests, firefighter's garments and vehicle safety devices, especially such as those deployed on school buses, slow moving vehicles, trucks, emergency response transport vehicles, etc. Passive light management as disclosed in, for example U.S. Pat. No. 6,446,571, and U.S. Pat. No. 6,656,566, is attractive because it has no moving parts or devices with components that periodically need to be serviced. However, even the passive light management approach, though less problematic than the active light management approach, leads to expensive products, such as safety garments and similar protective gear and object demarcation safety devices.
A key drawback of the passive light management approach is the permanent attachment of the reflective element to the item that needs to be highlighted for safety. Currently the reflective element is optionally sewn on the item, permanently adhered onto it via “iron on” (hot melt) adhesive, or attached to the item via some other semi-permanent or permanent adhesive.
Generally, when an adhesive is used to secure the reflective safety element to the item, a pressure sensitive adhesive (PSA) is used. This may or may not allow the reflective element to be repositionable. Alternatively, Velcro® Fasteners, or another hook and loop fastener or other type of mechanical method is used to provide the feature of detachability and reattach-ability to the reflective element. However, these types of fastening means either have to be permanently attached to both the article and the reflective element, or temporarily affixed employing, for example, a PSA.
A disadvantage to the use such an attachment method is the potential damage to the surface upon repositioning due to the adhesive residue left behind. Another disadvantage is the requirement of having an essentially flat, non-textured surface for adequate attachment. The PSA approach has a further disadvantage in that it allows for only a limited number of uses because the adhesive becomes contaminated or otherwise damaged after just a few uses, thereby rendering the reflective element ineffective for long-term reuse. Still another disadvantage is that the use of a PSA attachment is often limited to indoor applications because many PSAs are not weather resistant and therefore not suitable for outdoor use.
Even though the use of magnetic attachment has been disclosed, see U.S. Pat. No. 6,446,571, PSAs are employed to attach the magnet to the reflective element. Consequently, this patent does not entirely overcome the disadvantages discussed above.
Another approach is disclosed in U.S. Pat. No. 6,027,227 which discloses a foldable tarp with a plurality of active light emitting devices mechanically mounted onto retroreflective strips. The complex circuitry and the aforementioned power source requirement render the objects of the '227 unusable as magnetically repositionable reflective safety devices.